Template:Are You Sure/May 8

• ... that mathematician John Henry Constantine "Henry" Whitehead (1904–1960) was one of the founders of homotopy theory, which originated in algebraic topology as a systematic study of situations in which maps come with homotopies between them; and that J.J. Rotman, in his book on algebraic topology, as a tribute to Whitehead's intellect, stated: "There is a canard that every textbook of algebraic topology either ends with the definition of the Klein bottle or is a personal communication to J. H. C. Whitehead."?